JPH11143441A - Device and method for controlling image display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To display the graphics data whose pixel aspect ratio is 1:1 on a video monitor to display the TV image signal with excellent quality. SOLUTION: The resolution of the graphics data to be compositedly displayed with a DVD video is specified to be a value (848×480) which is horizontally larger than the resolution (720×480) of the DVD video so that the graphics data is displayed on a screen of a video monitor having a display aspect ratio of 1:1 on the screen of the video monitor having the display aspect ratio of 16:9. When the graphics data is displayed on the video monitor with the display aspect ratio of 16:9, the resolution of the graphics data is scaled down in the horizontal direction by a scaler 104d, and converted to 720×480.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display control device for combining graphics data and moving image data and displaying the combined data on a TV.

[0002]

2. Description of the Related Art In recent years, with the development of computer technology,
Various multimedia-compatible digital video players, set-top boxes, and the like that can be used by connecting to a home TV have been developed.

[0003] Such digital video players and set-top boxes are not only used for displaying computer graphics, but also for CDs (Compact Disks) and DVs.
D (Digital Versatile Disk)
It is possible to decode and reproduce the moving image data that has been digitally compressed and stored in the digital camera.

[0004] DVD is a new video disc standard that can record video information such as a movie with high image quality on an optical disc of the same size as a CD using moving picture coding called MPEG2. The DVD recording / reproducing method is based on the concept of variable rate coding from the viewpoint of securing both the image quality and the recording time for the capacity. The data amount of the variable rate coded data depends on the image quality of the original image, and the data amount increases in a scene with more intense motion. The moving image data stored on the DVD is created based on the same NTSC video signal as a home TV, and the image decoded and reproduced by the MPEG2 decoder becomes an interlaced scanning video signal.

Recently, advanced graphics processing such as three-dimensional graphics can be realized even in a home digital video player or set-top box by increasing the speed of a CPU and improving a graphics controller. The graphics data can interactively change the display image according to a user operation such as scrolling the screen freely. For this reason, it is desired to realize a new video with high entertainment properties by fusing graphics and a natural moving image of MPEG2 and displaying them in a composite manner.

[0006]

However, a satisfactory image cannot be obtained simply by combining graphics and moving images and displaying them on a TV. In order to display graphics on a TV with high quality, the following two factors need to be considered.

(1) Difference in Pixel Aspect Ratio The pixel aspect ratio of graphics data handled by a computer is usually one to one, but the pixel aspect ratio of a video signal displayed on a TV is not one to one.
The ratio between the horizontal direction and the vertical direction is different. Therefore, for example, if graphics data that appears to be a perfect circle on a display monitor of a computer is displayed on a TV screen as it is, there is a problem that the graphics data appears as a vertically long ellipse or a horizontally long ellipse.

(2) Difference in Signal Band While TV displays interlaced display, a computer display monitor displays non-interlaced display. The luminance band and color band of graphics data for non-interlaced display are wider than those of a video signal defined by TV. For this reason, if graphics data is interlaced on a TV,
A flicker phenomenon called flicker occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has been made to enable high-quality display of graphics data having a pixel aspect ratio of 1: 1 on a video monitor for displaying a TV video signal. It is an object of the present invention to provide an image display control device and an image display control method suitable for displaying a title in which a moving image is combined.

[0010]

The present invention converts graphics data having a pixel aspect ratio of 1: 1 into one.
In an image display control device for displaying a screen on a video monitor having a display aspect ratio of 6: 9, the resolution of the graphics data is such that the graphics data has no distortion on the screen of the video monitor having a display aspect ratio of 16: 9. As displayed, the resolution defined by the standard of the video signal for displaying on the video monitor is defined as a value obtained by expanding in the horizontal direction, and the graphics data is stored in the memory in which the graphics data is stored. Reading means; scaling means for executing scaling processing for reducing the graphics data in the horizontal direction so that the horizontal resolution of the read graphics data matches the horizontal resolution of the video signal; and the scaling means. Graphics scaled by Characterized by comprising a means for the screen display data to said video monitor.

In this image display control device, 16:
On a video monitor with a display aspect ratio of 9,
Considering that the pixel aspect ratio of a normal video signal such as a V video signal becomes horizontally long, a resolution expanded in the horizontal direction in advance is used as a new resolution standard for graphics data. Since the pixels of the graphics data are displayed horizontally on the video monitor, prepare graphics data with a large horizontal size in advance, reduce it horizontally by scaling, and then display it on the video monitor. Thereby, the difference in the pixel aspect ratio can be eliminated.

The horizontal resolution of the graphics data is:
A value determined based on the result of multiplication of the horizontal resolution value of the video signal and the pixel aspect ratio of the video signal. For example, in a multiple of 8 or 16, the horizontal resolution value of the video signal is It is preferable to determine a value closest to a value obtained by multiplying the pixel aspect ratio of the video signal. This makes it possible to achieve both efficient memory access for reading graphics data and the like and high-quality display of graphics data. Further, the offset address need not be a multiple of 8 or 16, but may be a multiple of an offset address indicating a vertical turn of the VRAM.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

First, a basic configuration of an image display control device according to an embodiment of the present invention will be described with reference to FIG. The image display control device is used as a digital video player, a set-top box, or the like, and provides a function of displaying computer graphics, a moving image, and a composite image of the graphics and the moving image on a home TV. . As shown, the image display control device includes a DVD drive 101 and an MPEG2 decoder 10.
2. Video memory (VRAM) 103, RGB palette 104a, color space converter 104b from RGB to YCrCb, filter 104c, scaler 104 used for pixel aspect ratio conversion of graphics
d. A scaler 105, an α blending circuit 106, a TV encoder 107, and the like for adjusting the moving image data size to the video window size for displaying the moving image data are provided.

The DVD drive 101 stores moving image data (D) stored on a DVD medium 100 composed of an optical disk.
VD video) and graphics data. The graphics data is used as a background image of moving image data. The graphics data is stored in a video memory (VRAM) by a DVD title playback application program executed by the CPU of the image display control device.
103 is written.

The video sources of the moving image data stored in the DVD medium 100 include a video source corresponding to a display aspect ratio of 4: 3 for standard TV and a display aspect ratio of 16: 9 for wide TV, HDTV and EDTV. Some of them correspond, but the resolution (horizontal resolution × vertical resolution) is 720 × 480 in both cases.

The moving image data includes main video (video), 16
Sub-pictures (sub-pictures) up to channels and audio (audio) up to eight channels can be included. In this case, these video, sub-picture, and audio are digitally compression-encoded and recorded according to the MPEG2 standard. In the MPEG2 standard, MPE
The data encoded in G2 can include other encoded data, and the encoded data is one M
Handled as a PEG2 program stream. MPEG2 is used for encoding video, and run-length encoding and DOLBY AC3 are used for encoding sub-pictures and audio, respectively. Even in this case,
The encoded video, sub-picture, and audio are treated as one MPEG2 program stream. The encoding processing of the MPEG2 standard is variable rate encoding, and the amount of information recorded / reproduced per unit time can be made different. Therefore, the more intense the scene, the more MPEG
By increasing the transfer rate of the stream, high-quality moving image reproduction becomes possible.

The video data stored in the DVD medium 100 includes data corresponding to a display aspect ratio of 4: 3 for standard TV, wide TV, HDTV, and EDTV.
There is a display corresponding to a display aspect ratio of 16: 9, and the maximum resolution (horizontal resolution × vertical resolution) is 720 × 480 in both cases.

On the other hand, the graphics data stored in the DVD medium 100 also has a resolution (horizontal resolution × vertical resolution) corresponding to a display aspect ratio of 4: 3 for standard TV.
= 640x480, wide TV, HDT
Resolution corresponding to 16: 9 display aspect ratio for V and EDTV (horizontal resolution × vertical resolution) = 848 × 4
Some have 80. The pixel aspect ratio of graphics data corresponding to either the display aspect ratio of 4: 3 or 16: 9 is 1: 1.

The resolution (848 × 480) corresponding to the display aspect ratio of 16: 9 is a new standard determined by the present inventor for displaying graphics data on a TV with high quality. By preparing graphics data enlarged in the horizontal direction in advance as a video source in this way, high-quality graphics data can be displayed on a TV with a pixel aspect ratio of 1: 1 only by simple scaling. .

M read from the DVD medium 100
The PEG2 program stream is sent to the MPEG2 decoder 102. The MPEG2 decoder 102 uses the MP
After separating the EG2 program stream into video data, sub-picture data, and audio data, they are decoded, synchronized, and output. The decoded video data and sub-picture data are combined and then sent to the scaler 105 as YCrCb format moving image data.

The scaler 105 is used to reduce the size of the moving image data (720 × 480) to match the size of the video window, and is used when the video window size is smaller than the size of the moving image data.

The α blending circuit 106 combines moving picture data and graphics data in pixel units.
The ratio of the combination of the moving image data and the graphics data for each pixel is determined by the α value. The α value is a parameter indicating the degree of transmission of each pixel of the graphics data, and the transmittance of each pixel of the moving image data is 1-α. Therefore, for example, the graphics data is displayed for the pixel of α = 1, and the moving image data is not displayed. Conversely, the graphics data is not displayed for the pixel of α = 0, and the moving image data is displayed.

The TV encoder 107 converts the image data synthesized by the α blending circuit 106 into an NTSC
Alternatively, the video signal is converted into a PAL video signal and displayed on the TV receiver 200 in an interlaced manner.

As the TV receiver 200, the standard T
V, or those compatible with wide TV, HDTV, and EDTV. A TV receiver that supports wide TV, HDTV, and EDTV can normally support both display modes of 4: 3 and 16: 9 as monitor modes. The switching of the monitor mode is performed in the TV receiver 200 in accordance with an instruction from the user input by a remote control operation or the like.

When the number of bits of graphics data per pixel rendered in the video memory (VRAM) 103 is 8 bits in the index color mode, the RGB palette 104a stores the 8 bits / pixel index color data in the RGB color palette. , G, and B are converted into 24-bit RGB color data, each having 8 bits. Also, the graphics data drawn on the video memory (VRAM) 103 may be an R bit of 16 bits / pixel or more.
If the data is GB color data, the RGB palette 104
a is used for color correction of RGB colors.

The color space converter 104b converts the RGB color data into YCr of the same television standard as the moving image data.
Convert to Cb data.

Filter 104c and scaler 104d
Is provided for high-quality display of graphics data for non-interlaced display drawn on the video memory (VRAM) 103 on the TV 200 for interlaced scanning. , A filtering process for reducing the luminance and chrominance signal bands in accordance with the video signal for TV 200, and a scaling process for pixel aspect ratio conversion.

The content of the scaling process executed by the scaler 104d is based on the relationship between the resolution of the graphics data and the display aspect ratio of the TV 200.
It is determined by an application program for D title reproduction or a display driver. The resolution of the graphics data can be read from the header information of the graphics data. In addition, TV
The display aspect ratio of 200 indicates that the application program for DVD title playback is
To enter the monitor mode of the TV 200 or the TV 200
The image display control device can automatically determine the monitor mode by automatically communicating with the TV 200 using an interface between the TV 200 and the image display control device.

[0030] RGB palette 104a, color space converter 104b, filter 104c, and scaler 104
The graphics data processing by d
3 is performed as follows on the graphics data.

For example, in a display period of an odd field, a data unit having three lines of graphics data including graphics data of an odd-numbered line to be displayed and graphics data of two even-numbered display lines sandwiching the graphics data. The data is alternately read out from the video memory (VRAM) 103 in a time-division manner and sequentially input pixel by pixel to the RGB palette 104a and the color space converter 104b, where it is converted into the same YCrCb format data as the moving image data.

Thereafter, for each of the three lines of data converted into the YCrCb format, filtering and scaling in the horizontal direction are performed in units of a predetermined number of pixels for each line by the filter 104c and the scaler 104.
d respectively. As a result, the pixel aspect ratio is expanded or reduced in the horizontal direction for each line of data, and a circle drawn as graphics data in the video memory (VRAM) 103 can be displayed on the TV 200 as a circle instead of an ellipse. .

Next, an example of a composite image of moving image data and graphics data will be described.

FIG. 2 shows a display example of content in which moving image data is displayed in a video window and graphics data is used as a background image of the video window. This content is used as an electronic encyclopedia, and on the graphics video used as the background video of the video window, the name and attribute of the searched object, image data matching the object, and screen operation Buttons are displayed, and the object itself is displayed as a natural moving image in the video window. In the example of FIG. 2, the object is “dolphin” and the image data on the graphics video is “seaweed”.

Further, both the moving image data and the graphics data can be combined and displayed in a full screen size. FIG. 3 shows a display example in this case.

In FIG. 3, a natural moving image of "dolphin" selected as an object and a graphics image including its name, attributes, image data, operation buttons, etc. are both synthesized and displayed in full screen size. .

Next, the definition of graphics data used in this embodiment will be described with reference to FIGS.

FIG. 4 shows the resolution 72 of the DVD video data.
The relationship between 0x480 and the pixel aspect ratio when the image is displayed on a TV having a display aspect ratio of 16: 9 is shown.

When the DVD video data having a resolution of 720 × 480 is displayed on a TV screen having a display aspect ratio of 16: 9, the pixel aspect ratio (X: Y) of the DVD video data can be obtained from the following equation.

720X: 480Y = 16: 9 X: Y = 32: 27 Thus, a TV having a display aspect ratio of 16: 9
Has a landscape pixel aspect ratio.

FIG. 5 shows a graphics resolution (848.times.48) required to display graphics data having a pixel aspect ratio of 1: 1 on a TV having a display aspect ratio of 16: 9 at a pixel aspect ratio of 1: 1.
0).

Here, the value 848 of the graphics horizontal resolution (horizontal size) is a multiple of 16,
The data closest to the value obtained by multiplying the horizontal resolution 740 of the video data 740 by 32/27 is adopted. By increasing the horizontal resolution of graphics to a multiple of 16, VRAM1
Address calculation for reading / writing graphics data with respect to the G.03 can be simplified.

Therefore, in practice, any of the following values can be used as the resolution of graphics data when a screen is displayed on a TV having a display aspect ratio of 16: 9.

(1) 848 × 480 (2) 864 × 480 (3) 832 × 480 Instead of a multiple of 16, a multiple of 8 can be used. Since the above numerical value of the resolution of the graphics data is calculated based on the resolution (720 × 480) and the pixel aspect ratio (32:27) when the DVD video is a video source of the NTSC system, the DVD video is In the case of a PAL video source, the resolution of the graphics data is a value corresponding to the resolution.

Also, even if it is not a multiple of 8 or 16, V
A value that is a multiple of the offset address indicating the vertical folding of the RAM may be used.

Next, referring to FIG.
A graphics scaling method in a case where DVD video data and graphics data are combined and displayed on a 6: 9 TV will be described.

As described above, in the present embodiment, the following two types are assumed as graphics data included in contents.

(1) Graphics data resolution for display aspect ratio 16: 9 = 848 × 480 (2) Graphics data for display aspect ratio 4: 3 Resolution = 640 × 480 Graphics data (8 for display aspect ratio 16: 9)
In the case of displaying (48 × 480), the graphics data is reduced in the horizontal direction by the scaler 104d and converted to the same 720 × 480 resolution as DVD video data. Then, the video data output from the MPEG2 decoder 102 and the scaled graphics data are combined by the α blending circuit 106 and displayed on the TV in the monitor mode 16: 9.

On a video monitor having a display aspect ratio of 16: 9, the pixels of the graphics data are displayed in such a manner as to be spread in the horizontal direction. However, graphics data having a horizontal size larger than the video data is prepared in advance. The difference in pixel aspect ratio can be eliminated by displaying it on a video monitor after reducing it horizontally by scaling.

When video data output from the MPEG2 decoder 102 is displayed in a video window, the resolution of the video data is converted by the scaler 105.

On the other hand, when displaying graphics data (640 × 480) for a display aspect ratio of 4: 3,
The graphics data is reduced in the horizontal direction by the scaler 104d, and has a resolution (5
40x480). Then, the video data output from the MPEG2 decoder 102 and the scaled graphics data are combined by the α blending circuit 106, and the T
V is displayed.

Also in this case, since the graphics data reduced in the horizontal direction by the scaler 104d is displayed on a video monitor having a display aspect ratio of 16: 9, the difference in the pixel aspect ratio can be eliminated.

Next, referring to FIG. 7, monitor mode 4:
A graphics scaling method in the case where DVD video data and graphics data are combined and displayed on a TV 3 will be described.

When displaying graphics data (848 × 480) for a display aspect ratio of 16: 9, a VRA of 540 pixels (540 × 480) in the center of the frame of the graphics data excluding the left and right regions in the frame is used.
M, which is converted to the same 720 × 480 resolution as the DVD video data by being horizontally expanded by the scaler 104d. With this horizontal scaling, the pixel aspect ratio of the graphics data becomes the same as that of the video data. MP
In the EG2 decoder 102, the 720 × 480 video data is pan-scanned, thereby obtaining 720 × 480 video data.
(For example, 540 × 480) is read out as an actual video output. Then, the video data in the pan scan mode and the scaled graphics data are combined by the α blending circuit 106 and displayed on the TV in the monitor mode 4: 3.

Since pixels of graphics data are displayed vertically on a video monitor having a display aspect ratio of 4: 3, a part of the graphics data is displayed on the video monitor after being expanded in the horizontal direction. This can eliminate the difference in pixel aspect ratio.

On the other hand, when displaying graphics data (640 × 480) for a display aspect ratio of 4: 3,
The graphics data is expanded in the horizontal direction by the scaler 104d, and the same 720x as the DVD video data.
It is converted to a resolution of 480. With this enlargement scaling, the pixel aspect ratio of the graphics data becomes the same as that of the video data. In the MPEG2 decoder 102, the 720x480 video data is pan-scanned, whereby a part (for example, 540x480) of the 720x480 video data is read as an actual video output. Then, the video data in the pan scan mode and the scaled graphics data are α
The images are synthesized by the blending circuit 106 and displayed on the TV in the monitor mode 4: 3.

As described above, in this embodiment, only horizontal scaling is performed on graphics data having a pixel aspect ratio of 1: 1 and the graphics data is converted into a pixel aspect ratio for a TV monitor without changing its vertical size. doing. Therefore, hardware for vertical scaling is not required, and cost can be reduced.

FIG. 8 shows a specific configuration example of the image display control device of FIG.

This image display control device is based on the DVD-
A DVD title can be reproduced using the ROM drive 101, and various application programs such as game software and a viewer can be executed. This image display control device includes a CPU 11, a host /
PCI bridge 12, main memory 13, mask ROM 14 for storing OS, I / O control gate array 15,
USB connector 16, LED 17 for displaying status on the control panel, various user operation switches 18 for configuring the control panel, infrared communication port 19, RS232C connector 20, system BI
In addition to a flash ROM 21 for storing an OS, a socket 22 for a flash memory card (SSFDC), a D / A converter 23, an AC3 decoder 24, and an audio mixer 25, the above-described DVD-ROM drive 101,
MPEG2 decoder 102, video memory (VRAM)
103 and an NTSC encoder 107 are provided.

The CPU 11 controls the operation of the entire system, and executes the operating system loaded into the main memory 13, application programs to be executed, and various driver programs.

The host / PCI bridge 12 is an LSI for bidirectionally converting a transaction between the processor bus 1 and the PCI bus 2, and includes a processor bus interface 121 and a PCI bus interface 123.
It has. Further, the host / PCI bridge 12 is provided with a memory controller 122 for controlling access to the main memory 13 and the mask ROM 14 according to a memory read / write transaction issued from the CPU 11 and another PCI bus master.

The I / O control gate array 15 is one LSI for controlling various I / O devices, and includes a PCI bus 2 and an internal PC as shown in FIG.
PCI bus interface 15 connecting I buses 2a
1. A PCI / ISA bridge 152 for connecting the internal PCI bus 2a and the internal ISA bus 2b is provided. The internal PCI bus 2a has a USB interface 153 for controlling peripheral devices such as an external keyboard connected to the USB connector 16, a bus master IDE controller 154 for controlling the DVD-ROM drive 101, and scaling and filtering of the graphics data described above. A display controller 155 for performing processing, α blending of graphics and moving image data, and the like, and an MPEG interface 156 for controlling an interface between the internal PCI bus 2a and the MPEG2 decoder 102 are connected.

The display controller 155 includes a memory controller 201 for controlling access to the video memory (VRAM) 103, various logical operations between the source and destination bitmaps, and enlargement / reduction of the bitmap in accordance with instructions from the CPU 11. (Block Block Transfer) Circuit 2
02, a graphics / video mixer 203, and a PCM audio controller 204. The graphics / video mixer 203 is the RGB palette 1 shown in FIG.
04a, color space converter 104b, filter 104
c, a graphics scaler 104d, a video scaler 105, an α blending circuit 106, and the like. The PCM audio controller 204 converts audio data such as sound effects accompanying graphics data into PCM audio data.
It is a PCM sound source that converts to audio data.

The flow of moving image data and graphics data in the system shown in FIG. 8 is as follows.

That is, the DVD playback control application program file is read from the DVD medium via the DVD drive 101 and loaded into the main memory 13. Then, under the control of the program, C
The PU 11 stores the graphics data used as the background image of the moving image data into the D
The data is read from the VD medium to the main memory 13, the data is drawn in the video memory (VRAM) 103, and the audio data is transferred to the PCM audio controller 204.

The graphics / video mixer 203 sends a video memory (VRA) through the memory controller 201.
M) Graphics data of a plurality of lines including the display target line is alternately read from the 103 in a time-division manner, and the above-described horizontal scaling processing and vertical filtering processing for non-interlace / interlace conversion are executed by a pipeline operation. The PCM audio controller 204 converts the audio data into PCM audio data and passes it to the D / A converter 23.

On the other hand, the moving image data is transferred from the DVD-ROM drive 101 to the MPEG2 decoder 102 via the main memory 13. MPEG2 decoder 102
In the first embodiment, the video and sub-picture included in the MPEG2 program stream are decoded,
Digital video data in rCb422 format is generated. The audio data included in the MPEG2 program stream is sent from the MPEG2 decoder 102 to the AC3 decoder 24 as it is, where it is decoded. The decoded YCrCb422 format digital video data is output to the graphics / video mixer 2
03 and alpha blended with the graphics data. Then, NTSC encoder 107
Video signal for V (composite signal or S video signal)
After that, the image is interlaced and displayed on the TV. The audio data decoded by the AC3 decoder 24 is combined with the audio data from the PCM audio controller 204 by the audio mixer 25 and sent to a TV audio input line or the like.

FIG. 9 shows a graphics / video mixer 2
03 and a specific circuit configuration around the same are shown.

The graphics / video mixer 203 includes:
As shown, a current buffer 301, a next buffer 302, a multiplexer 303, an RGB palette 3
04a, RGB / YCrCb color space converter 304
b, color key circuit 304c, current scaling
H filter 305, next scaling / H filter 306, delay circuit 307, YCrCb 444/42
2 conversion circuits 308 and 309, before line buffer 3
10, V filter 311, FIFO buffer 312a,
312b, an α blending circuit 313, a control register 314, and the like are provided.

The current buffer 301 and the next buffer 302 temporarily hold the display target line and the next line of graphics data which are alternately read out from the video memory (VRAM) 103 by the memory controller 201 in units of a predetermined data size in a time division manner. This is a buffer for For example, a video memory (VRA)
M) The graphics data stored in 103 is 16 bits / pixel, and the video memory (VRAM) 103
If the data bus is 32 bits, the graphics data of the display target line and the graphics data of the next line are read alternately in units of two pixels.

The multiplexer 303 alternately selects the current buffer 301 and the next buffer 302, and serially outputs the graphics data stored in the selected buffer in pixel units. This pixel data is sent to the RGB palette 304a and the color key circuit 304c.

The RGB palette 304a is composed of three color tables corresponding to R, B, and B, respectively, as shown in FIG. Each color table is composed of 256 entries and an address decoder that decodes 8-bit pixel data and selects one of the 256 entries. Each entry stores 8-bit color data.

When the graphics data stored in the VRAM 103 is 16 bits / pixel, each pixel data is divided into R = 5 bits, G = 6 bits, and B = 5 bits. The 5-bit R data is used as an upper bit portion of the 8-bit data input to the R color table. Similarly, the 6-bit B data and the 5-bit B data are also used as upper bits of the 8-bit data input to the G and B color tables, respectively. Thereby, when the graphics data stored in the VRAM 103 is 16 bits / pixel,
The RGB palette 304a functions as a color correction table for pixel data, and 24-bit color data is output from the RGB palette 304a.

On the other hand, if the graphics data stored in the VRAM 103 is 8-bit / pixel index color data, the index color data is commonly input to each of the R, B, and G color tables. It is converted to 24-bit color data.

The color key circuit 304c holds the correspondence between the color of the pixel data and the 4-bit α value.
An α value corresponding to the color of the input pixel data is output. This α value is sent to a delay circuit 307, where it is delayed by the time of color space conversion, horizontal scaling, and vertical filtering processing, and then
Α blending circuit 3 via FO buffer 312b
13 is sent.

RGB / YCrCb color space converter 30
4b converts RGB color data from the RGB palette 304a into 24-bit data corresponding to the YCrCb444 format of the video standard. The YCrCb data is sent to the current scaling / H filter 305 or the next scaling / H filter 306.

Current scaling / H filter 305
And the next scaling / H filter 306 are for performing horizontal filtering / scaling processing on graphics data of the display target line and the next line, respectively, and are 444 format YC.
The graphics data of the display target line converted to the rCb data is input to the current scaling / H filter 305, and the graphics data of the next line converted to the YCrCb data of the 444 format is input to the next scaling / H filter 306.

Current scaling / H filter 305
Are 444 belonging to a display target line that is continuously input
The YCrCb data in the format is firstly subjected to horizontal filtering processing for reducing the luminance and chrominance signal bands, and then sequentially performs calculations for horizontal scaling. This horizontal filtering process is executed by a product-sum operation using an FIR filter, and is realized by the circuit of FIG.

The horizontal filter circuit shown in FIG. 11 has a three-tap configuration. In order to perform a product-sum operation between three consecutive pixels, two delay circuits 511 and 512 for delaying data by one pixel each, Multipliers 513,
514, 515 and an adder 516. The multiplier value (coefficient) of each of the multipliers 513, 514, and 515 is determined by the value of the control parameter set in the control register 314.

The horizontal scaling processing is realized by thinning out the pixels subjected to the filter processing by the horizontal filter circuit of FIG. 11, or by continuously outputting the same pixels. The content of the horizontal scaling process to be executed is determined by the value of the scaling control parameter (H-CONT) set in the control register 314.
The value of the scaling control parameter (H-CONT) is
It is determined by the monitor mode and the resolution of the graphics source.

The pixels of the line to be displayed after the horizontal filtering and the scaling are YCrCb444 /
The data is sent to a 422 conversion circuit 308, where it is converted into 16-bit wide 422 format YCrCb data, and then input to a V filter 311.

Next scaling / H filter 306
Performs a horizontal filtering process for reducing the luminance and chrominance signal bands on the 444 format YCrCb data belonging to the continuously input next line, and then sequentially performs an operation for horizontal scaling. . This horizontal filter processing is executed by a product-sum operation using an FIR filter, and is realized by the circuit of FIG. Pixels of the line to be displayed after horizontal filtering and scaling are YCrC
b444 / 422 conversion circuit 309, where 16
It is converted to YCrCb data of 422 format with a bit width. The converted YCrCb data is supplied to a V filter 31.
1, and the Y data in the YCrCb data is stored in the before-line buffer 310 for use as the data one line before in the next scan.

The V filter 311 uses the data of the corresponding pixel position of the previous line held in the before-line buffer 310 every time the data of the corresponding pixel position for the display target line and the next line are prepared. Perform vertical filtering between lines.
This vertical filter processing is also executed by a product-sum operation using an FIR filter, and is realized by the circuit of FIG. The vertical filter circuit in FIG. 12 includes three multipliers 611, 612, and 613 and an adder 616 in order to perform a product-sum operation between three consecutive lines. The multiplier value of each of the multipliers 611, 612, and 613 is determined by the value of the control parameter set in the control register 314.

FIG. 1 shows the state of the vertical filtering process.
3 is shown.

FIG. 13 shows an example of the vertical filtering process in the case where the line L3 is a display target line. In order from the top pixel of each of the lines L2, L3, and L4, three pixels at the corresponding pixel positions are sequentially arranged. Are sequentially performed. As a result, graphics data for one line to be displayed in the odd field of the TV is generated. At the time of the next scan, an odd-numbered line next to the line L3, that is, the line L5 is a display target line, and vertical filtering is performed on three lines L4, L5, and L6.

The pixel data obtained by the vertical filtering is sent to the synchronization information insertion circuit (Gen656) 312c via the FIFO buffer 312a. The synchronization information insertion circuit (Gen656) 312c inserts synchronization information into the YCrCb data sequence,
This is for generating digital data in the same ITU-R656 format as D video data.

Then, in the α blending circuit 313, the graphics data and the DVD video data are synthesized according to the α value of the pixel position corresponding to the display target line. This synthesizing process is performed at a timing according to the synchronization signal of the DVD video data detected by the timing control circuit 204.

The control register 314 is a register readable and writable by the CPU 11, and sets the control parameters for designating the horizontal and vertical filter characteristics and the contents of the horizontal scaling processing as described above.

As described above, in the configuration of FIG. 9, graphics data of a plurality of lines including the display target line are alternately read in a time-division manner, sequentially subjected to the horizontal scaling process, and subjected to the horizontal scaling. By performing vertical filtering in units of data each time data at the same pixel position is aligned for multiple lines,
The horizontal scaling process and the vertical filtering process are executed in a pipeline manner. Thus, the graphics data read from the video memory (VRAM) 103 is
The scaling process and the vertical filtering process can be performed efficiently without using the off-screen area of the above. Therefore, high-quality graphics data can be displayed on a TV without preparing a video memory (VRAM) 103 having a particularly large memory bandwidth.

Next, a mechanism for setting a control parameter (scaling parameter) for horizontal scaling control in the control register 314 will be described with reference to FIG.

The DVD playback control application program determines from the header information included in the graphics data read from the DVD medium which graphics source has a resolution corresponding to a display aspect ratio of 16: 9 or 4: 3. Is detected, and the detection result is passed to the display driver.

The display driver operates in the monitor mode (16: 9,
Or 4: 3) and a scaling method is determined based on the display aspect ratio of the graphics data, and a scaling parameter for executing the scaling process by the scaling method is set in the control register 314.

FIG. 15 is a flowchart showing a procedure of a graphics scaling control method applied to graphics data.

First, the display aspect ratio of the TV monitor is determined (step S101). In the case of a 16: 9 monitor, if the graphics data has a display aspect ratio of 1
If it has a resolution (848 × 480) corresponding to 6: 9 (step S102), horizontal scaling processing from 848 × 480 to 720 × 480 is performed (step S103), and the graphics data corresponds to a display aspect ratio of 4: 3. Resolution (640x48
0) (step S102), 64
A horizontal scaling process from 0x480 to 540x480 is performed (step S104).

On the other hand, in the case of a 4: 3 monitor, if the graphics data has a resolution (848 × 480) corresponding to a display aspect ratio of 16: 9 (step S105), 540 horizontal pixels of 848 × 480 are selected. And a horizontal scaling process for enlarging it to 720 × 480 is executed (step S10).
6) Also, the graphics data has a display aspect ratio of 4:
If it has a resolution (640 × 480) corresponding to 3 (step S 105), the 640 × 480 to 72
Horizontal scaling processing to x480 is executed (step S107).

As described above, according to the present embodiment, graphics data having a horizontal size larger than the horizontal size specified by the video data standard is prepared, and the graphics data is set to the monitor mode. The pixel aspect ratio of the graphics data is adjusted to the video data by reducing / enlarging in the horizontal direction based on the video data. Therefore, a title in which graphics and moving images are combined can be displayed with high quality on a video monitor for displaying a TV video signal.

FIG. 16 shows a second example of the graphics / video mixer.

As shown, the graphics / video mixer includes a current buffer 301, a next buffer 302, a multiplexer 303, and a color palette 30.
4. Current scaling / H filter 305, Next scaling / H filter 306, Delay circuit 30
7, YCrCb444 / 422 conversion circuits 308, 30
9, before line buffer 310, V filter 31
1, a FIFO buffer 312, and an α blending circuit.

The current buffer 301 and the next buffer 302 temporarily store the graphics data of the display target line and the graphics data of the next line, which are alternately read out from the video memory (VRAM) 103 by the memory controller 201 in a predetermined data size unit in a time division manner. The target is a buffer to hold. For example, if the graphics data of the index color mode stored in the video memory (VRAM) 103 is 8 bits / pixel and the data bus of the video memory (VRAM) 103 is 32 bits, the graphics data of the display target line and the next The graphics data of the line is alternately read in units of 4 pixels.

The multiplexer 303 alternately selects the current buffer 301 and the next buffer 302, and outputs the index color mode graphics data stored in the selected buffer serially in pixel units. This pixel data is sent to the color palette 304.

As shown in FIG. 17, the color palette 304 decodes 256 entries and 8-bit pixel data input as an index value and selects one of the 256 entries. Address decoder. Each entry has 444
A set of 24-bit YCrCb data corresponding to the format and an 8-bit α value is set in advance. The 444 format YCrCb data output from the color palette 304 is stored in the current scaling
The signal is sent to the H filter 305 or the next scaling / H filter 306. The α value is sent to a delay circuit 307, where it is delayed by the time of horizontal scaling and vertical filtering processing, and
The data is sent to the α blending circuit 312 via the IFI buffer 312b.

Current scaling / H filter 305
And a next scaling / H filter 306 are for performing horizontal filtering / scaling processing on the graphics data of the display target line and the next line, respectively.
The graphics data of the display target line converted to the YCrCb data of the 44 format is input to the current scaling / H filter 305, and the graphics data of the display target line converted to the YCrCb data of the 444 format by the color palette 304 is subjected to the current scaling. Input to H filter 306.

Current scaling / H filter 305
Are 444 belonging to a display target line that is continuously input
The YCrCb data in the format is first subjected to horizontal filtering processing for reducing the luminance and color signal bands, and then sequentially performs calculations for horizontal scaling. This horizontal filtering is executed by a product-sum operation using an FIR filter.

The pixels of the line to be displayed after the horizontal filtering and the scaling are YCrCb444 /
After being sent to a 422 conversion circuit 308, where it is converted into 422 format YCrCb data,
11 is input.

Next scaling / H filter 306
Performs a horizontal filtering process for reducing the luminance and chrominance signal bands on the 444 format YCrCb data belonging to the continuously input next line, and then sequentially performs an operation for horizontal scaling. . This horizontal filtering is executed by a product-sum operation using an FIR filter.

The pixels of the display target line after the horizontal filtering and the scaling are YCrCb444 /
The data is sent to a 422 conversion circuit 309, where it is converted into 422 format YCrCb data. YCr after conversion
The Cb data is sent to the V filter 311 and its YC
The Y data in the rCb data is stored in the before-line buffer 310 for use as data one line before in the next scan.

The V filter 311 uses the data of the corresponding pixel position of the previous line held in the before-line buffer 310 every time the data of the corresponding pixel position for the display target line and the next line are prepared. Perform vertical filtering between lines.
This vertical filter processing is also executed by a product-sum operation using an FIR filter.

The pixel data obtained by the vertical filtering is sent to the α blending circuit 313 via the FIFO buffer 312a, and is synthesized with the YCrCb422 format moving image data according to the α value of the corresponding pixel position of the display target line.

Also, the current buffer 301 and the FIFO
A direct path is provided between the buffer 304 and the buffer 312a. By using the direct path, the palette 304, the scaling / H filters 305 and 30 are used.
6, and without passing through the V filter 311
O buffer 312a and α blending circuit 313
Can be sent directly to the NTSC encoder 106 via This direct path is used, for example, when a still image having a large number of colors such as 16 bits / pixel is drawn by the CPU 11 in the video memory 103. As described above, by changing the data processing path between the case of using the index color mode and the case of using data having a larger number of colors, it is possible to always obtain the optimum display quality. The route is selected, for example, by PC
This can be performed by switching the input of the FIFO buffer 312a according to the set value for the register of the I interface 155a.

As described above, in the configuration of FIG.
By using the line buffer 310 that holds the graphics data after scaling of the previous line to be displayed, the vertical filtering between the three lines can be performed simply by alternately reading out the two lines in a time-division manner. It becomes possible. Here, the case where the vertical filtering is performed between three lines is illustrated, but the vertical filtering can be performed between five lines.

FIG. 18 shows a software structure for dynamically changing the filter characteristics using the control register 314.

The operating system is provided with a filter setting function for receiving a filter characteristic change instruction from the application program as an application interface. When a filter characteristic change instruction is issued from the application program, it is displayed from the operating system. Passed to the driver. The display driver is a program for controlling the display controller, and sets a predetermined control parameter in the control register 314 according to a filter characteristic change instruction. As a result, the application program displays the display contents, ie, the video memory 10
By issuing a filter characteristic change instruction in accordance with the content to be drawn in 3, it becomes possible to dynamically change the filter characteristic between the character display portion and the image display portion, and the like. It is possible to automatically obtain a suitable filter characteristic.

FIG. 19 shows a third configuration example of the graphics / video mixer 203.

The graphics / video mixer is configured to perform vertical filtering between three lines without using a line buffer for holding graphics data of one line before, and a video memory (VRAM)
Three buffers respectively corresponding to three lines (display target line, next line, previous line) which are alternately read from 103 in a time-division manner, that is, a current buffer 401, a next buffer 402, and a before buffer 403.
Is provided. Also, for the scaling / H2 filter, three circuits corresponding to each of the three lines,
A current scaling / H filter 406, a next scaling / H filter 407, and a before scaling / H filter 408 are provided, and horizontal scaling of each of three lines is performed in parallel.

The V filter 413 is configured to perform a filtering process not only on the Y data but also on the Cr and Cb data. High quality display with less color fringing can be achieved as compared to a vertical filter using only Y data.

[0116]

As described above, according to the present invention, graphics data having a pixel aspect ratio of 1: 1 can be displayed in high quality on a video monitor for displaying a TV video signal, and graphics and moving images can be displayed. And a title display that combines the above. Further, the scaling process and the vertical filtering process can be efficiently performed on the graphics data read from the video memory without using the off-screen area of the video memory, and the graphics data can be displayed on the TV with high quality. .

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of an image display control device according to an embodiment of the present invention.

FIG. 2 is an exemplary view showing an example of a display screen by the image display control device of the embodiment.

FIG. 3 is an exemplary view showing another example of the display screen by the image display control device of the embodiment.

FIG. 4 shows a D used in the image display control device of the embodiment.
The figure which shows the relationship between the resolution of VD video data, and the pixel aspect ratio at the time of displaying the screen on TV which has a display aspect ratio of 16: 9.

FIG. 5 is an exemplary view showing the resolution of graphics data used in the image display control device of the embodiment.

FIG. 6 is an exemplary view for explaining a graphics scaling method in the case where DVD video data and graphics data are combined and displayed on a TV in monitor mode 16: 9 in the image display control device of the embodiment.

FIG. 7 is an exemplary view for explaining a graphics scaling method in a case where DVD video data and graphics data are combined and displayed on a TV in monitor mode 4: 3 in the image display control device of the embodiment.

FIG. 8 is an exemplary block diagram showing the system configuration of the image display control device of the embodiment.

FIG. 9 is an exemplary block diagram illustrating an example of a specific configuration of a graphics / video mixer provided in the image display control device according to the embodiment.

FIG. 10 is an exemplary view showing an example of a specific configuration of an RGB palette provided in the image display control device of the embodiment.

FIG. 11 is an exemplary view showing an example of a specific configuration of a horizontal filter circuit provided in the image display control device of the embodiment.

FIG. 12 is a diagram showing an example of a specific configuration of a vertical filter circuit provided in the image display control device of the embodiment.

FIG. 13 is an exemplary view for explaining the principle of a vertical filtering process used in the image display control device according to the embodiment;

FIG. 14 is an exemplary view showing a software configuration for setting scaling parameters in a control register provided in the image display control device of the embodiment.

FIG. 15 is an exemplary flowchart showing the procedure of graphics scaling processing applied to the image display control device of the embodiment.

FIG. 16 is a block diagram showing another configuration example of the graphics / video mixer provided in the image display control device of the embodiment.

FIG. 17 is a diagram showing a configuration example of a color palette provided in the graphics / video mixer of FIG. 16;

FIG. 18 is a view for explaining a mechanism for dynamically changing the filter characteristics of the horizontal / vertical filter circuits provided in the graphics / video mixer of FIG. 16;

FIG. 19 is an exemplary block diagram showing still another configuration of the graphics / video mixer provided in the image display control device of the embodiment.

[Explanation of symbols]

 101 DVD-ROM drive 102 MPEG2 decoder 103 Video memory 104a RGB palette 104b Color space converter 104c Filter 104d Scaler 106 Alpha blending circuit 301 Current buffer 302 Next buffer 303 Multiplexer 304a RGB palette 304b ... Color space converter 305 ... Current scaling / H filter 306 ... Next scaling / H filter 307 ... Delay circuit 308,309 ... YCrCb444 / 422 conversion circuit 310 ... Before line buffer 311 ... V filter

Claims (15)

[Claims] 1. An image display control device for displaying graphics data having a pixel aspect ratio of 1: 1 on a video monitor having a display aspect ratio of 16: 9, wherein the resolution of the graphics data is 16: 9. In order for the graphics data to be displayed without distortion on the screen of the video monitor having an aspect ratio, the resolution specified by the standard of the video signal to be displayed on the video monitor is specified to a value obtained by horizontally expanding the resolution. Means for reading the graphics data from a memory in which the graphics data is stored; and a means for reading the graphics data in a horizontal direction so that a horizontal resolution of the read graphics data matches a horizontal resolution of the video signal. Scale to perform scaling to reduce to An image display control device, comprising: a scaling unit; and a unit for displaying graphics data scaled by the scaling unit on a screen of the video monitor. 2. The video data according to claim 1, wherein the horizontal resolution of the graphics data is determined based on a result of multiplying a horizontal resolution value of the video signal by a pixel aspect ratio of the video signal. Image display control device. 3. The resolution of the video signal (horizontal x vertical)
Is 720 × 480, and the resolution (horizontal x vertical) of the graphics data is 8
The image display control device according to claim 1, wherein the image display control device is 48x480. 4. The resolution of the video signal (horizontal x vertical)
Is 720 × 480, and the resolution (horizontal x vertical) of the graphics data is 8
The image display control device according to claim 1, wherein the image display control device is 68x480. 5. The resolution of the video signal (horizontal x vertical)
Is 720 × 480, and the resolution (horizontal x vertical) of the graphics data is 8
The image display control device according to claim 1, wherein the image display control device is 32x480. 6. The image display according to claim 1, further comprising: means for synthesizing the graphics data scaled by the scaling means and the video signal and displaying a screen on the video monitor. Control device. 7. An image display control device for displaying graphics data having a pixel aspect ratio of 1: 1 on a video monitor having a display aspect ratio of 4: 3, wherein the resolution of the graphics data is 16: 9. The resolution defined by the video signal standard having an aspect ratio is defined as a value obtained by expanding the resolution in the horizontal direction. Means for reading the corresponding graphics data; scaling means for performing a scaling process for expanding the graphics data in the horizontal direction such that the horizontal resolution of the read graphics data matches the horizontal resolution of the video signal And this scaling means It said ring processed graphics data 4: an image display control apparatus characterized by comprising a means for screen display on a video monitor having a display aspect ratio of 3. 8. The video signal according to claim 7, wherein the horizontal resolution of the graphics data is determined based on a result of multiplying a value of a horizontal resolution of the video signal by a pixel aspect ratio of the video signal. Image display control device. 9. The resolution of the video signal (horizontal x vertical)
Is 720 × 480, and the resolution (horizontal x vertical) of the graphics data is 8
The image display control device according to claim 7, wherein the image display control device is 48x480. 10. A means for outputting a video signal having a display aspect ratio of 16: 9 in a pass scan mode, and combining graphics data scaled by the scaling means with a video signal output in the pass scan mode. 8. The image display control device according to claim 7, further comprising: means for displaying a screen on the video monitor. 11. An image display control apparatus for displaying graphics data having a display aspect ratio of 16: 9 or 4: 3 included in a video source on a video monitor having a display aspect ratio of 16: 9 or 4: 3. A means for reading the graphics data from a memory in which graphics data included in the video source is stored; and determining based on a type of graphics data included in the video source and a display aspect ratio of the video monitor. A scaling means for performing scaling processing for horizontally expanding or reducing graphics data read from the memory using a scaling method; and displaying the graphics data scaled by the scaling means on the video monitor. Means An image display control device comprising: 12. An image display control device for displaying, on a TV receiver, content including digitally compressed and encoded moving image data and graphics data used as a background image of the moving image data, wherein the recording includes recording the content. A drive device that drives a medium to read the content from the recording medium, a decoding device that receives moving image data included in the content read by the drive device, and decodes the moving image data; RGB of graphics data included
YCrCb corresponding to video signal for TV receiver
Color space conversion means for converting the graphics data into a color space; and scaling processing for expanding or reducing the graphics data in the horizontal direction in order to convert the pixel aspect ratio of the graphics data whose color space has been converted by the color space conversion means. And a means for combining the graphics data scaled by the scaling means with the moving image data decoded by the decoding device and displaying the synthesized data on the TV receiver. Image display control device. 13. An image display control method for displaying graphics data having a pixel aspect ratio of 1: 1 on a video monitor having a display aspect ratio of 16: 9, wherein the resolution of the graphics data is 16: 9. In order for the graphics data to be displayed without distortion on the screen of the video monitor having an aspect ratio, the resolution defined by the standard of the video signal to be displayed on the video monitor is specified to a value enlarged in the horizontal direction. The graphics data is read from a memory in which the graphics data is stored, and the graphics data is read out in a horizontal direction such that the horizontal resolution of the read graphics data matches the horizontal resolution of the video signal. Perform scaling process to reduce and scale Image display control method characterized by the screen grayed processed graphics data to the video monitor. 14. An image display control method for displaying graphics data having a pixel aspect ratio of 1: 1 on a video monitor having a display aspect ratio of 4: 3, wherein the resolution of the graphics data is 16: 9. The resolution defined by the video signal standard having an aspect ratio is defined as a value obtained by expanding the resolution in the horizontal direction. Reading corresponding graphics data, performing scaling processing for expanding the graphics data in the horizontal direction such that the horizontal resolution of the read graphics data matches the horizontal resolution of the video signal; Graphics scaled by Image display control method characterized by the screen displaying the Sudeta on the video monitor. 15. An image display control method for displaying graphics data having a display aspect ratio of 16: 9 or 4: 3 included in a video source on a video monitor having a display aspect ratio of 16: 9 or 4: 3. In the method, a scaling method to be performed on the graphics data is determined based on a type of graphics data included in the video source and a display aspect ratio of the video monitor, and the graphics data included in the video source is stored. The graphics data read from the memory, and using the determined scaling method, perform scaling processing for horizontally expanding or reducing the graphics data read from the memory. Graphic The image display control method characterized by the screen display data to said video monitor.